Abstract
A novel approach is presented to estimate the long-term contaminant
export from agricultural fields or small catchments due to soil erosion
using the spatial pattern of contaminant inventories in soil. This
approach uses a simple geographical information system based sediment
budget model, which provides a spatially distributed relative index of
erosion and deposition. The observed contaminant inventories in the soil
profile are related to this relative index of erosion and deposition.
The contaminant export from the area is then estimated as the difference
between the intercept of this relation, which represents the 'reference
contaminant inventory' in the absence of erosion and deposition, and the
mean observed soil contaminant inventory. This approach was applied to
quantify copper fungicides losses from two vineyard fields in
south-eastern France. The relative index of erosion and deposition
explained between 32% and 56% of the variation in the soil Cu
inventories. The respective average rates of Cu export from the two
vineyards studied were estimated to be 0.74 kg ha - 1 year
- 1 and 1.02 kg ha - 1 year - 1 . The
proposed method is especially useful in cases where 'reference sites',
where the contaminant input into soil has been equal to the field or
catchment under study but where no erosion or deposition has occurred,
are lacking. As effective reference sites are often absent in locations
where agricultural contaminants have been used, further refinement of
this model is warranted.
Original language | English |
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Pages (from-to) | 3-12 |
Journal | Geomorphology |
Volume | 79 |
Publication status | Published - 1 Sept 2006 |